WO2023142989A1

WO2023142989A1 - Flexible printed circuit board and touch-control display apparatus

Info

Publication number: WO2023142989A1
Application number: PCT/CN2023/071210
Authority: WO
Inventors: 肖云瀚; 李凡; 李聪聪; 王东; 石慧男
Original assignee: 京东方科技集团股份有限公司; 成都京东方光电科技有限公司
Priority date: 2022-01-29
Filing date: 2023-01-09
Publication date: 2023-08-03
Also published as: CN116567922A; US20240155761A1

Abstract

A flexible printed circuit board and a touch-control display apparatus. The flexible printed circuit board comprises a main flexible board and a bridging flexible board, wherein the main flexible board comprises a first main pad, a second main pad, a first signal line and a second signal line, and the bridging flexible board comprises a first bridging pad and a second bridging pad; the first main pad comprises at least two first solder joints, the second main pad comprises at least two second solder joints, the first bridging pad comprises at least two third solder joints, and the second bridging pad comprises at least two fourth solder joints; and the first solder joints are connected to the third solder joints, and the second solder joints are connected to the fourth solder joints. The flexible printed circuit board further comprises an auxiliary line, wherein a first signal line is connected to one first solder joint, a second signal line is connected to one second solder joint, and the auxiliary line is connected to one first solder joint or second solder joint.

Description

Flexible printed circuit board and display touch device

This application claims the priority of the Chinese patent application filed with CNIPA on January 29, 2022, with the application number 202210112906.7, and the title of the invention is "Flexible Printed Circuit Board and Display Touch Device", the content of which should be understood as being incorporated by reference. included in this application.

technical field

The present disclosure relates to but not limited to the field of display technology, and in particular refers to a flexible printed circuit board and a display touch device.

Background technique

With the rapid development of display technology, touch screen (Touch Screen) has gradually spread in people's life. According to the structure, the touch screen can be divided into Add on Mode, On Cell, In Cell, etc. According to the working principle, the touch screen can be divided into capacitive, resistive, infrared, surface acoustic wave and so on. Capacitive On Cell type includes display panel, touch panel and flexible circuit board (Flexible Printed Circuit, referred to as FPC). The touch panel is set on the light-emitting side of the display panel, and the display panel and touch panel are connected to external devices through the flexible circuit board. .

Contents of the invention

The following is an overview of the topics described in detail in this article. This summary is not intended to limit the scope of the claims.

In one aspect, the present disclosure provides a flexible printed circuit board, including a main flexible board and a bridging flexible board, the main flexible board at least includes a first main pad, a second main pad, at least one first signal line and at least one A second signal line, the bridging flexible board at least includes a first bridging pad, a second bridging pad and at least one connection line; the first main pad includes at least two first soldering points, and the second The main pad includes at least two second pads, the first signal line is connected to a first pad, and the second signal line is connected to a second pad; the first bridge pad includes at least two a third welding point, the second bridging pad includes at least two fourth welding points, the first end of the connecting line is connected to a third welding point, the second end of the connecting line is connected to a fourth Solder point connection; the first solder point is connected to the third solder point through soldering, and the second soldering point is connected to the fourth soldering point through soldering; the flexible printed circuit board also includes a first auxiliary line , any one or more of the second auxiliary line, the third auxiliary line and the fourth auxiliary line; the first end of the first auxiliary line is connected to the first signal line, and the first end of the first auxiliary line The two ends are connected to another first welding point; the first end of the second auxiliary line is connected to the second signal line, and the second end of the second auxiliary line is connected to another second welding point; The first end of the third auxiliary line is connected to the connection line, the second end of the third auxiliary line is connected to another third welding point; the first end of the fourth auxiliary line is connected to the connection line connected, the second end of the fourth auxiliary line is connected to another fourth welding point.

In an exemplary embodiment, the main flexible board includes a touch driving circuit and at least one terminal, the first end of the first signal line is connected to the terminal, and the second end of the first signal line is connected to the terminal. The first pad of the first main pad is connected, the first end of the second signal line is connected to the touch drive circuit, the second end of the second signal line is connected to the second main pad The second solder joint connection.

In an exemplary embodiment, the first main pad includes a plurality of first solder joints, the plurality of first solder joints are arranged in a matrix to form a solder joint array, and the plurality of first solder joints include the At least one first functional solder joint inside and at least one first non-functional solder joint located outside the array of solder joints, the first signal line is connected to the first functional solder joint, and the first The auxiliary line is connected to the first non-functional solder joint.

In an exemplary embodiment, the second main pad includes a plurality of second solder joints, and the plurality of second solder joints are arranged in a matrix to form a solder joint array, and the plurality of second solder joints include those located in the solder joint array. At least one second functional soldering point inside and at least one second non-functional soldering point located outside the array of soldering points, the second signal line is connected to the second functional soldering point, the first The auxiliary line is connected to the second non-functional solder joint.

In an exemplary embodiment, the first bridging pad includes a plurality of third solder joints, the plurality of third solder joints are arranged in a matrix to form a solder joint array, and the plurality of third solder joints include the At least one third functional soldering point inside and at least one third non-functional soldering point located outside the array of soldering points, the connection line is connected to the third functional soldering point, and the third auxiliary line Connect with the third non-functional solder joint.

In an exemplary embodiment, the second bridging pad includes a plurality of fourth pads, the plurality of fourth pads are arranged in a matrix to form a pad array, and the multiple fourth pads include a pad located in the pad array At least one fourth functional soldering point inside and at least one fourth non-functional soldering point located outside the array of soldering points, the connection line is connected to the fourth functional soldering point, and the fourth auxiliary line connected to the fourth non-functional solder joint.

In an exemplary embodiment, the bridging flexible board includes a connection line area, a first pad area, and a second pad area, and the connection line area is disposed between the first pad area and the second pad area Between; the connecting line is set in the connecting line area, the first bridge pad is set in the first pad area, and the second bridge pad is set in the second pad area; the A first connection point where the third auxiliary line is connected to the connection line is located in the connection line area, and/or a second connection point where the fourth auxiliary line is connected to the connection line is located in the connection line area.

In an exemplary embodiment, the bridging flexible board includes a connection line area, a first pad area, and a second pad area, and the connection line area is disposed between the first pad area and the second pad area Between, the connection line is arranged in the connection line area; the first pad area includes a first pad area and a first dispensing area, and the first pad area is provided with the first bridging pad, The first dispensing area is arranged on the periphery of the first welding spot area; the second pad area includes a second welding spot area and a second dispensing area, and the second welding spot area is provided with the first welding spot area. Two bridging pads, the second dispensing area is arranged on the periphery of the second welding point area; the first connection point where the third auxiliary line is connected to the connection line is located in the first dispensing area, And/or, the second connection point where the fourth auxiliary line is connected to the connecting line is located in the second dispensing area.

In an exemplary embodiment, the center-to-center distance between adjacent first welding points is 1.05 mm to 1.25 mm; and/or, the center-to-center distance between adjacent second welding points is 1.05 mm to 1.25 mm; and /or, the center-to-center distance between adjacent third welding points is 1.05 mm to 1.25 mm; and/or, the center-to-center distance between adjacent fourth welding points is 1.05 mm to 1.25 mm.

In an exemplary embodiment, the first bridging pad further includes at least one through hole disposed between the adjacent third pads; and/or, the second bridging pad It also includes at least one through hole, the through hole is arranged between the adjacent fourth welding points.

In an exemplary embodiment, the size of the through hole is less than or equal to 0.1 mm, and the size of the through hole refers to the maximum value of the distance between any two points on the edge of the through hole.

In an exemplary embodiment, the center distance between the through hole and the adjacent third welding spot is 0.55mm to 0.65mm; and/or, the center distance between the through hole and the adjacent fourth welding spot 0.55mm to 0.65mm.

In an exemplary embodiment, in a plane perpendicular to the flexible printed circuit board, the bridging flexible board is disposed on the main flexible board, and the bridging flexible board includes a first bridging flexible board disposed on the main flexible board The green oil layer, the first bridging conductive layer arranged on the side of the first bridging green oil layer away from the main flexible board, the bridging substrate layer arranged on the side of the first bridging conductive layer away from the main flexible board, The second bridging conductive layer arranged on the side of the bridging base material layer away from the main flexible board and the second bridging green oil layer arranged on the side of the second bridging conductive layer away from the main flexible board; A bridging conductive layer is only provided in the connecting line area of the bridging flexible board.

In an exemplary embodiment, between the edge of the third solder joint close to the connecting line area and the edge of the first bridging conductive layer in the connecting line area close to the third solder joint The distance is greater than or equal to 1.0mm, and/or, the edge of the fourth solder joint near the connection line area is the same as the first bridging conductive layer in the connection line area close to the fourth solder joint The distance between the edges of the sides is greater than or equal to 1.0 mm.

In an exemplary embodiment, the main flexible board includes a shielding layer, a cover layer disposed on the shielding layer, a first main conductive layer disposed on the side of the covering layer away from the shielding layer, a first main conductive layer disposed on the shielding layer, The first main conductive layer is away from the main substrate layer on the side of the shielding layer, the second main conductive layer is arranged on the side of the main substrate layer away from the shielding layer, and the second main conductive layer is arranged on the side of the second main conductive layer. The main green oil layer on the side away from the shielding layer; the first bridging green oil layer of the bridging flexible board is in direct contact with the main green oil layer.

On the other hand, the present disclosure also provides a display touch device, including a touch display panel and the aforementioned flexible printed circuit board, the touch display panel includes an active area and a binding area located on one side of the active area , the binding area includes a binding pin area, and the flexible printed circuit board is connected to the binding pin area.

Other aspects will become apparent upon reading and understanding the drawings and detailed description.

Description of drawings

The accompanying drawings are used to provide a further understanding of the technical solutions of the present disclosure, and constitute a part of the specification, and are used together with the embodiments of the present disclosure to explain the technical solutions of the present disclosure, and do not constitute limitations to the technical solutions of the present disclosure. The shapes and sizes of the various components in the drawings do not reflect true scale, but are only intended to illustrate the present disclosure.

FIG. 1 is a schematic plan view of a display touch device;

FIG. 2 is a schematic plan view showing a binding area in a touch device;

FIG. 3 is a schematic plan view showing the edge area of a touch device;

FIG. 4 is a schematic cross-sectional structural view showing an effective area in a touch device;

5 is a schematic diagram of a flexible printed circuit board binding connection;

6 is a schematic plan view of the main flexible board in a flexible printed circuit board;

7 is a schematic plan view of a bridging flexible board in a flexible printed circuit board;

8 is a schematic plan view of a main flexible board according to an exemplary embodiment of the present disclosure;

FIG. 9a is a schematic diagram of the arrangement of multiple solder joints in an exemplary pad of the present disclosure;

FIG. 9b is a schematic diagram of the arrangement of multiple solder joints in another exemplary pad of the present disclosure;

Fig. 10 is an enlarged view of area A in Fig. 8;

Figure 11 is an enlarged view of area B in Figure 8;

12 is a schematic plan view of a bridging flexible board according to an exemplary embodiment of the present disclosure;

Figure 13 is an enlarged view of area C in Figure 12;

Fig. 14 is an enlarged view of area D in Fig. 12;

15 is a schematic plan view of another bridging flexible board according to an exemplary embodiment of the present disclosure;

Fig. 16 is a schematic plan view of another bridging flexible board according to an exemplary embodiment of the present disclosure;

17 is a schematic cross-sectional structure diagram of a flexible circuit board according to an exemplary embodiment of the present disclosure;

Fig. 18 is a schematic cross-sectional structure diagram of another flexible circuit board according to an exemplary embodiment of the present disclosure;

Fig. 19 is a schematic cross-sectional structure diagram of yet another flexible circuit board according to an exemplary embodiment of the present disclosure;

Fig. 20 is a schematic cross-sectional structure diagram of yet another bridging flexible board according to an exemplary embodiment of the present disclosure.

Explanation of reference signs:

10—the main flexible board; 11—the first main pad; 12—the second main pad;

20—bridge flexible board; 21—first bridge pad; 22—second bridge pad;

31—sensing lead; 32—drive lead; 33—display lead;

40—flexible printed circuit board; 41—sensing signal line; 50—touch drive circuit;

51—the first driving signal line; 52—the second driving signal line; 60—auxiliary device;

61—display signal line; 70—connector; 71—first auxiliary line;

72—second auxiliary line; 73—third auxiliary line; 74—fourth auxiliary line;

81—connection line; 90—through hole; 91—first connection point;

92—second connection point; 93—solder; 100—effective area;

101—substrate; 102—drive circuit layer; 103—light emitting structure layer;

104—encapsulation structure layer; 105—buffer layer; 106—first metal grid layer;

107—insulation layer; 108—the second metal grid layer; 109—protective layer;

110—the first touch unit; 111—the first touch electrode; 112—the first connection part;

120—the second touch unit; 121—the second touch electrode; 122—the second connection part;

200—binding area; 201—first fan-out area; 202—bending area;

203—second fan-out area; 204—anti-static area; 205—driver chip area;

206—binding pin area; 210—connection line area; 211—first pad area;

211-1—the first solder joint area; 211-2—the first dispensing area; 212—the second pad area;

212-1—the second solder joint area; 212-2—the second dispensing area; 300—the edge area;

401—terminal area; 402—circuit area; 403—connection area;

411—outer shielding layer; 412—covering layer; 413—first main conductive layer;

414—the main substrate layer; 415—the second main conductive layer; 416—the main green oil layer;

417—main shielding layer.

422—the first bridging conductive layer; 424—the second bridging conductive layer;

425—Second bridging green oil layer.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present disclosure clearer, the embodiments of the present disclosure will be described in detail below in conjunction with the accompanying drawings. Note that an embodiment may be embodied in many different forms. Those skilled in the art can easily understand the fact that the means and contents can be changed into various forms without departing from the gist and scope of the present disclosure. Therefore, the present disclosure should not be interpreted as being limited only to the contents described in the following embodiments. In the case of no conflict, the embodiments in the present disclosure and the features in the embodiments can be combined arbitrarily with each other. In order to keep the following description of the embodiments of the present disclosure clear and concise, the present disclosure omits detailed descriptions of some known functions and known components. The accompanying drawings of the embodiments of the present disclosure only relate to the structures involved in the embodiments of the present disclosure, other structures can refer to the general design

The proportions of the drawings in the present disclosure can be used as a reference in the actual process, but are not limited thereto. For example, the width-to-length ratio of the channel, the thickness and spacing of each film layer, and the width and spacing of each signal line can be adjusted according to actual needs. The number of pixels in the display substrate and the number of sub-pixels in each pixel are not limited to the numbers shown in the figure. The figures described in the present disclosure are only structural schematic diagrams, and one mode of the present disclosure is not limited to the accompanying drawings. The shape or value shown in the figure, etc.

Ordinal numerals such as "first", "second", and "third" in this specification are provided to avoid confusion of constituent elements, and are not intended to limit the number.

In this specification, for convenience, "middle", "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner" are used , "external" and other words indicating the orientation or positional relationship are used to illustrate the positional relationship of the constituent elements with reference to the drawings, which are only for the convenience of describing this specification and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation , are constructed and operate in a particular orientation and therefore are not to be construed as limitations on the present disclosure. The positional relationship of the constituent elements changes appropriately according to the direction in which each constituent element is described. Therefore, it is not limited to the words and phrases described in the specification, and may be appropriately replaced according to circumstances.

In this specification, unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be interpreted in a broad sense. For example, it may be a fixed connection, or a detachable connection, or an integral connection; it may be a mechanical connection, or an electrical connection; it may be a direct connection, or an indirect connection through an intermediate piece, or an internal communication between two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present disclosure in specific situations.

In this specification, "electrically connected" includes the case where constituent elements are connected together through an element having some kind of electrical effect. The "element having some kind of electrical action" is not particularly limited as long as it can transmit and receive electrical signals between connected components. Examples of "elements having some kind of electrical function" include not only electrodes and wiring but also switching elements such as transistors, resistors, inductors, capacitors, and other elements having various functions.

The triangle, rectangle, trapezoid, pentagon, or hexagon in this specification are not strictly defined, and may be approximate triangles, rectangles, trapezoids, pentagons, or hexagons, etc., and there may be some small deformations caused by tolerances. There can be chamfers, arc edges, deformations, etc.

In the present specification, "parallel" refers to a state where the angle formed by two straight lines is -10° to 10°, and therefore includes a state where the angle is -5° to 5°. In addition, "perpendicular" means a state in which the angle formed by two straight lines is 80° to 100°, and therefore also includes an angle of 85° to 95°.

"About" in the present disclosure refers to a numerical value that is not strictly limited, and is within the range of process and measurement errors.

Capacitive On Cell type touch panels are mainly divided into mutual capacitance (Mutual Capacitance) structure and self capacitance (Self Capacitance) structure. The mutual capacitance structure is composed of the first touch electrode and the second touch electrode to form mutual capacitance. , using the change of mutual capacitance for position detection, the self-capacitance structure is composed of the touch electrode and the human body to form self-capacitance, and the change of self-capacitance is used for position detection. The self-capacitive touch panel has a single-layer structure and has the characteristics of low power consumption and simple structure. The mutual-capacitance touch panel has a multi-layer structure and has the characteristics of multi-touch.

The display touch device may include a display panel disposed on a base and a touch panel disposed on the display panel. The display panel may be a Liquid Crystal Display (LCD for short) panel, or an Organic Light Emitting Diode (OLED for short) display panel, or a plasma (PDP) display panel, or an electrophoretic display (EPD) display panel. In exemplary embodiments, the display panel may be an OLED display panel. OLED is an active light-emitting display device, which has the advantages of self-illumination, wide viewing angle, high contrast, low power consumption, and extremely high response speed. With the continuous development of display technology, flexible display devices (Flexible Display), which use OLED as a light-emitting device and are signal-controlled by Thin Film Transistor (TFT for short), have become mainstream products in the display field. According to product requirements such as flexible folding and narrow frame, the existing OLED-based touch structure adopts the flexible multi-layer overlay surface type (FMLOC for short) structure, and the display structure and touch structure are all integrated on the substrate. The touch panel is set on the encapsulation layer of the OLED backplane to form an on-cell structure, which has the advantages of lightness, thinness and foldability, and can meet the needs of products such as flexible folding and narrow bezels.

FIG. 1 is a schematic plan view of a display touch device. The touch panel is arranged on the display panel to form an FMLOC structure. In a plane parallel to the touch panel, the touch panel may include an active area (AA) 100 , a binding area 200 on one side of the active area 100 , and an edge area 300 on the other side of the active area 100 . For the stacked display panel and touch panel, the effective area can be either the touch area of the touch panel or the display area of the display panel. Both the touch area and the display area in the following description refer to the effective area. In an exemplary embodiment, the active area 100 includes at least a plurality of touch electrodes regularly arranged, the edge area 300 includes at least a plurality of touch leads, and the binding area 200 includes at least leads for connecting the touch leads to an external control device. foot.

In exemplary embodiments, the touch panel may be a mutual capacitance structure. The active area 100 may include a plurality of first touch units 110 and a plurality of second touch units 120, the first touch units 110 have a line shape extending along the first direction D1, and the plurality of first touch units 110 extend along the first direction D1. The two directions D2 are arranged sequentially, the second touch units 120 have a line shape extending along the second direction D2, and the plurality of second touch units 120 are arranged sequentially along the first direction D1, and the first direction D1 intersects the second direction D2. Each first touch unit 110 may include a plurality of first touch electrodes 111 and first connecting parts 112 arranged in sequence along the first direction D1, the first touch electrodes 111 and the first connecting parts 112 are arranged alternately and connected in sequence . Each second touch unit 120 may include a plurality of second touch electrodes 121 arranged in sequence along the second direction D2, the plurality of second touch electrodes 121 are arranged at intervals, and adjacent second touch electrodes 121 pass through the second The connection parts 122 are connected to each other. In an exemplary embodiment, the film layer where the second connecting portion 122 is located is different from the film layer where the first touch electrode 111 and the second touch electrode 121 are located. The first touch electrodes 111 and the second touch electrodes 121 are alternately arranged in a third direction D3, and the third direction D3 intersects the first direction D1 and the second direction D2.

In an exemplary embodiment, a plurality of first touch electrodes 111, a plurality of second touch electrodes 121 and a plurality of first connecting parts 112 can be arranged on the touch layer in the same layer, and can be formed by the same patterning process. In other words, the first touch electrodes 111 and the first connecting portion 112 may be an integral structure connected to each other. The second connection part 122 may be disposed on the bridging layer to connect adjacent second touch electrodes 121 to each other through via holes, and an insulating layer is disposed between the touch layer and the bridging layer. In some possible implementation manners, multiple first touch electrodes 111, multiple second touch electrodes 121 and multiple second connecting parts 122 can be arranged on the same layer on the touch layer, and the second touch electrodes 121 and the second The two connecting parts 122 may be an integral structure connected to each other, and the first connecting part 112 may be disposed on a bridging layer to connect adjacent first touch electrodes 111 to each other through via holes.

In exemplary embodiments, the first touch electrodes may be driving (Tx) electrodes, and the second touch electrodes may be sensing (Rx) electrodes. Alternatively, the first touch electrodes may be sensing (Rx) electrodes, and the second touch electrodes may be driving (Tx) electrodes.

In an exemplary embodiment, the shapes of the first touch electrodes and the second touch electrodes may include any one or more of the following: triangle, square, rectangle, rhombus, parallelogram, trapezoid, pentagon, hexagon , the present disclosure is not limited here.

In an exemplary embodiment, the first touch electrodes and the second touch electrodes may be in the form of transparent conductive electrodes. In another exemplary embodiment, the first touch electrode and the second touch electrode may be in the form of a metal grid, the metal grid is formed by interweaving a plurality of metal wires, the metal grid includes a plurality of grid patterns, and the grid A pattern is a polygon formed by a plurality of metal lines. The first touch electrode and the second touch electrode in the form of a metal grid have the advantages of small resistance, small thickness, and fast response speed.

FIG. 2 is a schematic plan view showing a binding area in a touch device. As shown in FIG. 2 , in an exemplary embodiment, the binding area 200 may be located on one side of the active area 100, and along the direction (second direction D2) away from the active area 100, the binding area 200 may include sequentially arranged The first fan-out area 201 , the bending area 202 , the second fan-out area 203 , the anti-static area 204 , the driving chip area 205 and the binding pin area 206 . The first fan-out area 201 can be provided with a plurality of touch leads and signal transmission lines, and the signal transmission lines can at least include a first power supply line (VDD), a second power supply line (VSS) and a plurality of data transmission lines, and the plurality of data transmission lines are configured as The data line (Data Line) of the display panel is connected in a fan-out (Fanout) manner, and the first power line VDD and the second power line VSS are configured to connect to the high-level power line and the low-level power line of the display panel respectively. The bending area 202 can be provided with grooves, and the grooves are configured to bend the second fan-out area 203 , the antistatic area 204 , the driver chip area 205 and the binding pin area 206 to the back of the active area 100 . The second fan-out area 203 can be provided with a plurality of touch leads and a plurality of data transmission lines led out in a fan-out manner. The anti-static area 204 may be provided with an anti-static circuit configured to eliminate static electricity. The driver chip area 205 can be provided with a source driver circuit (Driver IC), and the source driver circuit is configured to be connected to a plurality of data transmission lines in the second fan-out area 203. The binding pin area 206 may be provided with at least a plurality of pins (which may be referred to as gold fingers), and the plurality of pins are configured to be bound and connected to a flexible printed circuit board (Flexible Printed Circuit board, FPC for short).

FIG. 3 is a schematic diagram showing a planar structure of an edge region in a touch device. As shown in FIG. 3 , in an exemplary embodiment, besides the side where the binding area 200 is located, the edge area 300 may be located on other sides of the active area 100 . In an exemplary embodiment, taking the first touch electrode 111 as a sensing (Rx) electrode and the second touch electrode 121 as a driving (Tx) electrode as an example, multiple sensing leads 31 and multiple drive leads 32. In an exemplary embodiment, the first end of the sensing lead 31 is connected to the sensing electrode, the second end of the sensing lead 31 extends to one side of the bonding area 200 along the edge region 300 , and the first end of the driving lead 32 is connected to the driving electrode. The electrodes are connected, the second end of the driving wire 32 extends to the other side of the bonding area 200 , and the sensing wire 31 and the driving wire 32 together form a touch wire.

FIG. 4 is a schematic cross-sectional structure diagram of an active area in a display touch device, illustrating the structure of three sub-pixels. As shown in FIG. 4 , on a plane perpendicular to the display touch device, the touch panel can be disposed on the display panel. In an exemplary embodiment, the display panel may include a driving circuit layer 102 disposed on the base 101, a light emitting structure layer 103 disposed on the side of the driving circuit layer 102 away from the base 101, and a light emitting structure layer 103 disposed on a side away from the base 101. encapsulation structure layer 104 .

In exemplary embodiments, the substrate may be a flexible substrate, or may be a rigid substrate. The driving circuit layer 102 of each sub-pixel may include a plurality of transistors and storage capacitors constituting a pixel driving circuit. In FIG. 4 , each pixel driving circuit includes a transistor and a storage capacitor as an example for illustration. In an exemplary embodiment, the driving circuit layer 102 of each sub-pixel may include: a first insulating layer disposed on the substrate; an active layer disposed on the first insulating layer; a second insulating layer covering the active layer; The gate electrode and the first pole plate arranged on the second insulating layer; the third insulating layer covering the gate electrode and the first pole plate; the second pole plate arranged on the third insulating layer; the first pole plate covering the second pole plate Four insulation layers, the second insulation layer, the third insulation layer and the fourth insulation layer are provided with via holes, the via holes expose the active layer; the source electrode and the drain electrode arranged on the fourth insulation layer, the source electrode and the drain electrode The poles are respectively connected to the active layer through via holes; the flat layer covering the aforementioned structure has via holes opened on the flat layer, and the drain electrodes are exposed through the via holes. The active layer, the gate electrode, the source electrode and the drain electrode form a drive transistor, and the first plate and the second plate form a storage capacitor.

In exemplary embodiments, the light emitting structure layer 103 may include an anode, a pixel definition layer, an organic light emitting layer, and a cathode. The anode is arranged on the flat layer, and is connected to the drain electrode of the driving transistor through the via hole opened on the flat layer; the pixel definition layer is arranged on the anode and the flat layer, and a pixel opening is arranged on the pixel definition layer, and the pixel opening exposes the anode, organic The light-emitting layer is connected to the anode through the pixel opening, and the cathode is connected to the organic light-emitting layer. In an exemplary embodiment, the organic light-emitting layer may include an light-emitting layer (EML), and one or more of the following film layers: a hole injection layer (HIL), a hole transport layer (HTL), a hole blocking layer (HBL) ), electron blocking layer (EBL), electron transport layer (ETL) and electron injection layer (EIL). Driven by the voltage of the anode and the cathode, the luminescence characteristics of organic materials are used to emit light according to the required grayscale.

In an exemplary embodiment, the encapsulation structure layer 104 may include a stacked first encapsulation layer, a second encapsulation layer, and a third encapsulation layer, the first encapsulation layer and the third encapsulation layer may use inorganic materials, and the second encapsulation layer may Organic materials are used, and the second encapsulation layer is arranged between the first encapsulation layer and the third encapsulation layer, which can ensure that external water vapor cannot enter the light emitting structure layer 103 .

In an exemplary embodiment, on a plane perpendicular to the display touch device, the touch panel may include a buffer (Buffer) layer 105 disposed on the side of the encapsulation structure layer 104 away from the substrate 101, and disposed on the buffer layer 105 away from the substrate 101 The first metal grid (1st Metal Mesh, TMA for short) layer 106 on one side is arranged on the insulating layer 107 on the side of the first metal mesh layer 106 away from the base 101, and is arranged on the second insulating layer 107 on the side away from the base 101. The second metal mesh (2st Metal Mesh, TMB for short) layer 108 is disposed on the protective layer 109 on the side of the second metal mesh layer 108 away from the substrate 101.

In an exemplary embodiment, the buffer layer 105 and the insulating layer 107 can use any one or more of silicon oxide (SiOx), silicon nitride (SiNx) and silicon oxynitride (SiON), and can be a single layer, Multiple layers or composite layers. The first metal grid layer 106 and the second metal grid layer 108 can use metal materials, such as any one of silver (Ag), copper (Cu), aluminum (Al), titanium (Ti) and molybdenum (Mo) Or more than one, or alloy materials of the above metals, the protective layer 109 can be made of organic materials.

In an exemplary embodiment, the first metal grid layer 106 may be called a bridging layer, the second metal grid layer 108 may be called a touch layer, and a plurality of first touch electrodes, second touch electrodes and first touch electrodes The connecting part can be arranged on the touch layer in the same layer, and the second connecting part can be arranged on the bridging layer to connect adjacent second touch electrodes to each other through via holes.

Fig. 5 is a schematic diagram of a binding connection of a flexible printed circuit board, Fig. 6 is a schematic plan view of a main flexible board in a flexible printed circuit board, and Fig. 7 is a schematic plan view of a bridging flexible board in a flexible printed circuit board . In an exemplary embodiment, along a direction (first direction D1) parallel to the edge of the binding area, the binding area 200 can be divided into a first side area, a middle area, and a second side area, and the binding area edge is the binding area. The fixed area is adjacent to the edge of one side of the touch area. The left side of the binding area mentioned in the following description refers to the first side area of the binding area, the right side of the binding area refers to the second side area of the binding area, and the middle part of the binding area refers to the area on the left side of the binding area. The middle area between the right side of the binding area. In an exemplary embodiment, the binding pin area 206 in the binding area 200 may include a first pin area located in a first side area, a middle pin area located in a middle area, and a second pin area located in a second side area. The pin area, the first pin area, the middle pin area and the second pin area all include a plurality of pins.

In an exemplary embodiment, a plurality of sensing leads 31 are introduced from the frame area to the left side of the binding area, extend to the first pin area on the left side of the binding area, and correspond to multiple pins in the first pin area connect. A plurality of driving leads 32 are introduced from the frame area to the right side of the binding area, extend to the second pin area on the right side of the binding area, and are correspondingly connected to a plurality of pins in the second pin area. A plurality of display leads 33 are introduced from the source driver circuit D-IC located in the middle of the bonding area to the middle pin area, and are correspondingly connected to multiple pins in the middle pin area.

As shown in FIGS. 5 to 7 , in an exemplary embodiment, the flexible printed circuit board 40 may include a main flexible board 10 and a bridging flexible board 20 , a main pad may be arranged on the main flexible board 10 , and a bridging flexible board 20 may be A bridge pad is provided, and the bridge pad can be welded on the main pad by molten solder paste to form a double-layer bridge type flexible printed circuit board.

In an exemplary embodiment, the main flexible board 10 of the flexible printed circuit board 40 may be located on the side of the binding area 200 away from the active area 100, along the direction (second direction D2) away from the active area 100, the main flexible board 10 It may include a terminal area 401 , a circuit area 402 and a connection area 403 arranged in sequence.

In an exemplary embodiment, the terminal area 401 may include a plurality of terminals, and the plurality of terminals are correspondingly bound and connected to the plurality of pins in the binding pin area. Multiple terminals in the terminal area 401 can be regularly arranged along the first direction D1, and the terminal area 401 can be divided into a first terminal area, a middle terminal area and a second terminal area. The position of the first terminal area corresponds to the position of the first pin area of the binding area, and the multiple terminals in the first terminal area are correspondingly connected to the multiple pins in the first pin area. The position of the central terminal area corresponds to the position of the central pin area of the binding area, and multiple terminals in the central terminal area are correspondingly connected to multiple pins in the central area. The position of the second terminal area corresponds to the position of the second pin area of the binding area, and the multiple terminals of the second terminal area are correspondingly connected to the multiple pins of the second pin area.

In an exemplary embodiment, the circuit area 402 may at least include a first main pad 11, a second main pad 12, a touch driving circuit (Touch IC) 50, an auxiliary device 60, a plurality of sensing signal lines 41, a plurality of A first driving signal line 51 , a plurality of second driving signal lines 52 and a plurality of display signal lines 61 . Along the first direction D1, the touch drive circuit 50 can be located on the left side of the circuit area 402, the auxiliary device 60 can be located on the right side of the circuit area 402, and the first main pad 11 and the second main pad 12 can be located on the auxiliary device 60 away from the side of the terminal area 401 . In an exemplary embodiment, the first main pad 11 and the second main pad 12 are configured to be connected to the bridging pads on the bridging flexible board 20 , and the touch driving circuit 50 is configured to be connected to a plurality of sensing signal lines 41 Connected to a plurality of second driving signal lines 52 , the auxiliary device 60 is configured to be connected to a plurality of display signal lines 61 .

In an exemplary embodiment, the connection area 403 may at least include a connector (Connector) 70 and a plurality of display signal lines 61 , and the connector 70 is configured to be connected to the plurality of display signal lines 61 . Along the first direction D1 , the width of the connection region 403 may be smaller than the width of the circuit region 402 , and the connection region 403 may be located on the right side of the circuit region 402 . In an exemplary embodiment, the connector 70 may be located at an end of the connection area 403 away from the circuit area 402 . In an exemplary embodiment, the connector may serve as an external connection port, and the connector may be a board-to-board (Board-to-board, BTB for short) connector.

In an exemplary embodiment, the first ends of the plurality of sensing signal lines 41 are correspondingly connected to the plurality of terminals in the first terminal area, through the plurality of terminals in the first terminal area and the plurality of pins in the first pin area and A plurality of induction leads 31 on the left side of the binding area are correspondingly connected. The second ends of the plurality of sensing signal lines 41 extend to the touch driving circuit 50 and are connected to the touch driving circuit 50, thereby realizing the connection between the touch driving circuit 50 and the plurality of sensing leads 31 in the binding area, so that the touch driving The circuit 50 can provide touch sensing signals to the plurality of sensing leads 31 . Since the first terminal area and the touch driving circuit 50 are located on the left side of the circuit area 402 , the plurality of sensing signal lines 41 can be directly connected to the touch driving circuit 50 .

In an exemplary embodiment, the first main pad 11 may include a plurality of first pads, and the second main pad 12 may include a plurality of second pads. The first ends of the plurality of first drive signal lines 51 are correspondingly connected to the plurality of terminals in the second terminal area, through the plurality of terminals in the second terminal area and the plurality of pins in the second pin area and the plurality of binding areas. The driving leads 32 are correspondingly connected. The second ends of the plurality of first driving signal lines 51 extend to the first main pad 11 and are correspondingly connected to the plurality of first pads on the first main pad 11 . The first ends of the plurality of second driving signal lines 52 are connected to the touch driving circuit 50, the second ends of the plurality of second driving signal lines 52 extend to the second main pad 12, and are connected to the second main pad 12. The plurality of second solder joints are correspondingly connected.

In an exemplary embodiment, since the second terminal area is located on the right side of the circuit area 402, and the touch driving circuit 50 is located on the left side of the circuit area 402, the first driving signal line 51 and the second driving signal line 52 need to use a bridge The flexible boards 20 are connected to each other, extend from the right side of the circuit area 402 to the left side of the circuit area 402 and cross a plurality of display signal lines 61, so as to realize the connection between the touch driving circuit 50 and the plurality of driving leads 32 in the binding area, so that The touch driving circuit 50 provides touch driving signals to the plurality of driving wires 32 .

In an exemplary embodiment, the first ends of the plurality of display signal lines 61 are correspondingly connected to the plurality of terminals in the middle terminal area, and pass through the plurality of terminals in the middle terminal area and the plurality of pins in the middle pin area and the binding area A plurality of display leads 33 are correspondingly connected. A part shows that the second end of the signal line 61 extends directly from the circuit area 402 to the connection area 403, and is connected with the connector 70 located in the connection area; The connector 70 is connected, thus realizing the connection between the connector 70 and the plurality of display leads 33 in the binding area, so that the external control device provides display signals to the plurality of display leads 33 through the connector 70 .

In an exemplary embodiment, the bridging flexible board 20 is configured to be connected with the first main pad 11 and the second main pad 12 on the main flexible board 10 . The bridging flexible board 20 may at least include a first bridging pad 21, a second bridging pad 22 and a plurality of connection lines 81, the first bridging pad 21 may include a plurality of third soldering points, and the second bridging pad 22 may include A plurality of fourth welding points, the first ends of the plurality of connection lines 81 may correspond to the plurality of third welding points connected to the first bridge pads 21, and the second ends of the plurality of connection lines 81 may be correspondingly connected to the second bridge pads 22, realize the corresponding connection of the multiple third welding points and the multiple fourth welding points through the multiple connection lines 81.

In an exemplary embodiment, the plurality of third solder joints of the first bridge pad 21 and the multiple first solder joints of the first main pad 11 are correspondingly welded by molten solder paste, and the multiple solder joints of the second bridge pad 22 A fourth solder joint and a plurality of second solder joints of the second main pad 11 are correspondingly welded by molten solder paste, so that a plurality of first drive signal lines 51 and a plurality of second drive signal lines on the main flexible board 10 52 are correspondingly connected by bridging the flexible board 20 .

The study found that the existing flexible circuit boards have problems such as poor connection, one of the main reasons is that the solder joints are empty (Open NG) caused by solder joints or lack of tin. Further research found that one of the main reasons for empty soldering is the deformation of the area where the main pad and bridge pad are located on the flexible circuit board, resulting in two forms of solder joints, convex and concave, so that the main pad and bridge pad are deformed. The distance between the solder joints is different, and some solder paste solder joints are disconnected, resulting in empty soldering.

The present disclosure provides a flexible printed circuit board. The flexible printed circuit board may include a main flexible board and a bridge flexible board, the main flexible board includes at least a first main pad, a second main pad, at least one first signal line and at least one second signal line, the bridging The flexible board at least includes a first bridge pad, a second bridge pad and at least one connection line. The first main pad includes at least two first pads, the second main pad includes at least two second pads, the first signal line is connected to one first pad, and the second The signal line is connected with a second soldering point. The first bridging pad includes at least two third pads, the second bridging pad includes at least two fourth pads, the first end of the connection line is connected to a third pad, the The second end of the connecting wire is connected with a fourth welding point. The first soldering point is connected to the third soldering point through soldering, and the second soldering point is connected to the fourth soldering point through soldering. The flexible printed circuit board further includes any one or more of the first auxiliary line, the second auxiliary line, the third auxiliary line and the fourth auxiliary line; the first end of the first auxiliary line is connected to the first auxiliary line connected to the signal line, the second end of the first auxiliary line is connected to another first solder point; the first end of the second auxiliary line is connected to the second signal line, and the first end of the second auxiliary line The two ends are connected to another second welding point; the first end of the third auxiliary line is connected to the connecting line, and the second end of the third auxiliary line is connected to another third welding point; the first end of the third auxiliary line is connected to the other third welding point; The first ends of the four auxiliary wires are connected to the connection wires, and the second ends of the fourth auxiliary wires are connected to another fourth welding point. ,

FIG. 8 is a schematic plan view of a main flexible board in the flexible printed circuit board of an exemplary embodiment of the present disclosure. In an exemplary embodiment, the main flexible board may at least include a first main pad 11, a second main pad 12, a touch driving circuit 50, an auxiliary device 60, a plurality of terminals, a plurality of sensing signal lines 41, a plurality of A first driving signal line 51 , a plurality of second driving signal lines 52 and a plurality of display signal lines 61 .

In an exemplary embodiment, a plurality of terminals may be regularly arranged along the first direction D1, and the plurality of terminals are configured to be correspondingly connected to a plurality of pins in the binding area. The first main pad 11 may include a plurality of first pads configured to be correspondingly connected to a plurality of first driving signal lines 51 . The second main pad 12 may include a plurality of second pads configured to be correspondingly connected to a plurality of second driving signal lines 52 . In an exemplary embodiment, the first driving signal line 51 may serve as a first signal line of the present disclosure, and the second driving signal line 52 may serve as a second signal line of the present disclosure.

In an exemplary embodiment, the first ends of the plurality of display signal lines 61 are correspondingly connected to a plurality of terminals, and the second ends of the plurality of display signal lines 61 are connected to a connector (not shown). In an exemplary embodiment, the display signal line 61 may be directly connected to the connector, or may be connected to the connector through the auxiliary device 60 , which is not limited in this disclosure.

In an exemplary embodiment, the main flexible board may not be provided with auxiliary devices, and the disclosure is not limited herein.

In an exemplary embodiment, the first ends of the plurality of sensing signal lines 41 are correspondingly connected to a plurality of terminals, and the second ends of the plurality of sensing signal lines 41 extend to the touch driving circuit 50 and are connected to the touch driving circuit 50 .

In an exemplary embodiment, the first ends of the plurality of first driving signal lines 51 are correspondingly connected to a plurality of terminals, the second ends of the plurality of first driving signal lines 51 extend to the first main pad 11, and are connected to the first A plurality of first pads on the main pad 11 are correspondingly connected. The first ends of the plurality of second driving signal lines 52 are connected to the touch driving circuit 50, the second ends of the plurality of second driving signal lines 52 extend to the second main pad 12, and are connected to the second main pad 12. The plurality of second solder joints are correspondingly connected.

In an exemplary embodiment, a plurality of first pads on the first main pad 11 are correspondingly connected to a plurality of second pads on the second main pad 12 through a bridging flexible board to realize multiple first drive signals The line 51 is correspondingly connected to the second driving signal line 52 and straddles a plurality of display signal lines 61 .

Fig. 9a is a schematic diagram of the arrangement of multiple welding points in an exemplary pad of the present disclosure. As shown in FIG. 9 a , in an exemplary embodiment, the pad may include 25 solder points, and the 25 solder points may be arranged in a manner of 7 rows and 7 columns to form a solder point array. Row 1, Row 3, Row 5, and Row 7 all include four solder joints arranged in sequence along the first direction D1, and Row 2, Row 4, and Row 6 include four solder joints along the first direction D1. The three solder joints are arranged in sequence, and the solder joints in two adjacent rows are arranged alternately. The first column, the third column, the fifth column and the seventh column all include four solder joints arranged in sequence along the second direction D2, and the second column, the fourth column and the sixth column all include four welding points along the second direction D2 Three solder points are arranged in sequence, and the solder points in two adjacent columns are arranged alternately.

In an exemplary embodiment, the solder joints located inside the solder joint array may be referred to as functional solder joints, and the solder joints located outside the solder joint array may be referred to as non-functional solder joints. For example, functional solder joints may include: solder joints 2-2, solder joints 2-4, solder joints 2-6, solder joints 3-3, solder joints 3-5, solder joints 4-2, solder joints 4-4 , solder joint 4-6, solder joint 5-3, solder joint 5-5, solder joint 6-2, solder joint 6-4 and solder joint 6-6. As another example, the non-functional solder joints may include: solder joints 1-1, solder joints 1-3, solder joints 1-5, solder joints 1-7, solder joints 3-1, solder joints 3-7, and solder joints 5 -1, solder joint 5-7, solder joint 7-1, solder joint 7-3, solder joint 7-5 and solder joint 7-7.

Fig. 9b is a schematic diagram of the arrangement of multiple solder joints in another exemplary solder pad of the present disclosure. As shown in Figure 9b, the pad can include 25 solder joints, and the 25 solder joints can be arranged in 7 rows and 7 columns to form a solder joint array. The number of solder joints and the solder joint array of the pad are the same as those shown in Figure 9a The discs are basically similar, the difference is that the positions of the 25 welding points in FIG. 9b are mirror-symmetrical to the positions of the 25 welding points in FIG. 9a with respect to the second direction D2.

In an exemplary embodiment, the shape of the solder joints can be circular, square, rectangular or polygonal, etc., and the size of the solder joints can be less than or equal to 0.5mm. The size of the solder joints refers to the distance between any two points on the edge of the solder joints. The maximum distance of . For example, when the shape of the solder joint is circular, the diameter of the solder joint may be about 0.25 mm, 0.3 mm, 0.35 mm, and so on.

In an exemplary embodiment, the first center-to-center distance L1 between two adjacent welding points in the first direction D1 may be about 1.05mm to 1.25mm, and between two adjacent welding points in the second direction D2 The first center-to-center distance L1 may be about 1.05 mm to 1.25 mm, and the first center-to-center distance L1 is the distance between the geometric center of one solder joint and the geometric center of another solder joint.

In an exemplary embodiment, the number and arrangement of solder points on the first main pad and the second main pad can be set according to actual needs, which is not limited in the present disclosure.

In an exemplary embodiment, the first main pads may be arranged with the first solder joints in the arrangement shown in FIG. 9 a , and the second main pads may be arranged with the second solder joints in the arrangement shown in FIG. 9 b .

In an exemplary embodiment, the main flexible board may further include at least one first auxiliary line 71, the first end of the first auxiliary line 71 is connected to the first driving signal line 51, the second end of the first auxiliary line 71 is connected to the second A first solder joint of the main pad 11 is connected.

In an exemplary embodiment, the plurality of first solder joints may include at least one first functional solder joint located inside the solder joint array and at least one first non-functional solder joint located outside the solder joint array. A first end of the first driving signal line 51 is connected to a terminal, and a second end of the first driving signal line 51 is connected to a first functional pad. A first end of the first auxiliary line 71 is connected to the first driving signal line 51 , and a second end of the first auxiliary line 71 is connected to at least one first non-functional solder joint.

FIG. 10 is an enlarged view of area A in FIG. 8 . Taking the structure shown in FIG. 9a as an example of five first driving signal lines and the first main pad, the connection between the first driving signal line and the first pad will be described in detail below. As shown in FIG. 10, the five first driving signal lines may include a first driving sub-line 51-1, a second driving sub-line 51-2, a third driving sub-line 51-3, and a fourth driving sub-line 51-4. and the fifth driving sub-line 51-5, the five first auxiliary lines may include the first auxiliary sub-line 71-1, the second auxiliary sub-line 71-2, the third auxiliary sub-line 71-3, the fourth auxiliary sub-line 71-4 and the fifth auxiliary strand 71-5.

In an exemplary embodiment, the first end of the first driving sub-line 51-1 is connected to a terminal, and the second end of the first driving sub-line 51-1 extends toward the first main pad 11, and is connected to the first main pad 11. The functional pads 3 - 3 in the third row and third column on the pad 11 are connected. The first end of the first auxiliary sub-line 71-1 is connected to the first driving sub-line 51-1, and the second end of the first auxiliary sub-line 71-1 extends toward the first main pad 11, and is connected to the first main pad 11 The non-functional solder joints 1-1 in the first row and first column on the pad 11 are connected. In this way, the first driving sub-line can be connected to the two first pads on the first main pad by using the first auxiliary sub-line to form a "two (pad) to one (signal line)" connection.

In an exemplary embodiment, the first end of the second driving sub-line 51-2 is connected to a terminal, and the second end of the second driving sub-line 51-2 extends toward the first main pad 11, and is connected to the first main pad 11. The functional pads 3-5 in the third row and fifth column on the pad 11 are connected. The first end of the second auxiliary sub-line 71-2 is connected to the second driving sub-line 51-2, and the second end of the second auxiliary sub-line 71-2 extends toward the first main pad 11 and is connected to the first main pad 11. The non-functional solder joints 1-7 in row 1 and column 7 on pad 11 are connected. In this way, the second driving sub-line can be connected to the two first pads on the first main pad by using the second auxiliary sub-line to form a "two-to-one" connection.

In an exemplary embodiment, the first end of the third driving sub-line 51-3 is connected to a terminal, and the second end of the third driving sub-line 51-3 extends toward the first main pad 11, and is connected to the first main pad 11. The functional pads 4-4 in the fourth row and fourth column on the pad 11 are connected. The first end of the third auxiliary sub-line 71-3 is connected to the third driving sub-line 51-3, and the second end of the third auxiliary sub-line 71-3 extends toward the first main pad 11, and is connected to the first main pad 11 The non-functional solder joints 3-7 on the third row and seventh column on the pad 11 are connected. In this way, the third driving sub-line can be connected to the two first pads on the first main pad by using the third auxiliary sub-line to form a "two-to-one" connection.

In an exemplary embodiment, the first end of the fourth driving sub-line 51-4 is connected to a terminal, and the second end of the fourth driving sub-line 51-4 extends toward the first main pad 11, and is connected to the first main pad 11. The functional pads 5 - 5 in the fifth row and fifth column on the pad 11 are connected. The first end of the fourth auxiliary sub-line 71-4 is connected to the fourth driving sub-line 51-4, and the second end of the fourth auxiliary sub-line 71-4 extends toward the first main pad 11, and is connected to the first main pad 11. The non-functional solder joints 7-7 in row 7 and column 7 on pad 11 are connected. In this way, the fourth driving sub-line can be connected to the two first pads on the first main pad by using the fourth auxiliary sub-line to form a "two-to-one" connection.

In an exemplary embodiment, the first end of the fifth driving sub-line 51-5 is connected to a terminal, and the second end of the fifth driving sub-line 51-5 extends toward the first main pad 11, and is connected to the first main pad 11. The functional pads 5 - 3 in the fifth row and third column on the pad 11 are connected. The first end of the fifth auxiliary sub-line 71-5 is connected to the fifth driving sub-line 51-5, and the second end of the fifth auxiliary sub-line 71-5 extends toward the first main pad 11, and is connected to the first main pad 11. The non-functional solder joint 7-1 in the 7th row and 1st column on the pad 11 is connected. In this way, the fifth driving sub-line can be connected to the two first pads on the first main pad by using the fifth auxiliary sub-line to form a "two-to-one" connection.

In an exemplary embodiment, at least one functional soldering point may be provided between the functional soldering point connected to the first driving signal line and the non-functional soldering point connected to the auxiliary line connected to the first driving signal line .

In an exemplary embodiment, the main flexible board may further include at least one second auxiliary line 72, the first end of the second auxiliary line 72 is connected to the second driving signal line 52, the second end of the second auxiliary line 72 is connected to the first The second solder joints of the two main pads 12 are connected.

In an exemplary embodiment, the plurality of second solder joints may include at least one second functional solder joint located inside the solder joint array and at least one second non-functional solder joint located outside the solder joint array. The first end of the second driving signal line 52 is connected to the touch driving circuit, and the second end of the second driving signal line 52 is connected to a second functional pad. A first end of the second auxiliary line 72 is connected to the second driving signal line 52 , and a second end of the second auxiliary line 72 is connected to at least one second non-functional solder joint.

FIG. 11 is an enlarged view of area B in FIG. 8 . Taking the structure shown in FIG. 9 b as an example of five second driving signal lines and the second main pad, the connection between the second driving signal lines and the second pads will be described in detail below. As shown in FIG. 11, the five second driving signal lines may include a sixth driving sub-line 52-6, a seventh driving sub-line 52-7, an eighth driving sub-line 52-8, and a ninth driving sub-line 52-9. and the tenth driving sub-line 52-10, the five second auxiliary lines may include the sixth auxiliary sub-line 72-6, the seventh auxiliary sub-line 72-7, the eighth auxiliary sub-line 72-8, the ninth auxiliary sub-line 72-9 and the tenth auxiliary sub-line 72-10.

In an exemplary embodiment, the first end of the sixth driving sub-line 52-6 is connected to the touch driving circuit, and the second end of the sixth driving sub-line 52-6 extends toward the second main pad 12, and is connected to the second main pad 12. The functional pads 3 - 3 in the third row and third column on the two main pads 12 are connected. The first end of the sixth auxiliary sub-line 72-6 is connected to the sixth driving sub-line 52-6, and the second end of the sixth auxiliary sub-line 72-6 extends toward the second main pad 12, and is connected to the second main pad 12. The non-functional solder joints 1-1 on the first row and first column on the pad 12 are connected. In this way, the sixth driving sub-line is connected to the two second pads on the second main pad by using the sixth auxiliary sub-line to form a "two-to-one" connection.

In an exemplary embodiment, the first end of the seventh driving sub-line 52-7 is connected to the touch driving circuit, the second end of the seventh driving sub-line 52-7 extends toward the second main pad 12, and is connected to the second main pad 12. The functional pads 3-5 in the third row and fifth column on the two main pads 12 are connected. The first end of the seventh auxiliary sub-line 72-7 is connected to the seventh driving sub-line 52-7, and the second end of the seventh auxiliary sub-line 72-7 extends toward the second main pad 12, and is connected to the second main pad 12. The non-functional solder joints 1-7 in row 1 and column 7 on pad 12 are connected. In this way, the seventh driving sub-line is connected to the two second pads on the second main pad by using the seventh auxiliary sub-line to form a "two-to-one" connection.

In an exemplary embodiment, the first end of the eighth driving sub-line 52-8 is connected to the touch driving circuit, and the second end of the eighth driving sub-line 52-8 extends toward the second main pad 12, and is connected to the second main pad 12. The functional pads 4-4 on the 4th row and 4th column on the two main pads 12 are connected. The first end of the eighth auxiliary sub-line 72-8 is connected to the eighth driving sub-line 52-8, and the second end of the eighth auxiliary sub-line 72-8 extends toward the second main pad 12, and is connected to the second main pad 12. The non-functional solder joints 3-7 in row 3 and column 7 on pad 12 are connected. In this way, the eighth driving sub-line can be connected to the two second pads on the second main pad by using the eighth auxiliary sub-line to form a "two-to-one" connection.

In an exemplary embodiment, the first end of the ninth driving sub-line 52-9 is connected to the touch driving circuit, the second end of the ninth driving sub-line 52-9 extends toward the second main pad 12, and is connected to the second main pad 12. The functional pads 5-5 in the fifth row and fifth column on the two main pads 12 are connected. The first end of the ninth auxiliary sub-line 72-9 is connected to the ninth driving sub-line 52-9, and the second end of the ninth auxiliary sub-line 72-9 extends toward the second main pad 12, and is connected to the second main pad 12. The non-functional solder joints 7-7 in row 7 and column 7 on pad 12 are connected. In this way, the ninth driving sub-line can be connected to the two second pads on the second main pad by using the ninth auxiliary sub-line to form a "two-to-one" connection.

In an exemplary embodiment, the first end of the tenth driving sub-line 52-10 is connected to the touch driving circuit, and the second end of the tenth driving sub-line 52-10 extends toward the second main pad 12, and is connected to the second main pad 12. The functional pads 5 - 3 in the fifth row and third column on the two main pads 12 are connected. The first end of the tenth auxiliary sub-line 72-10 is connected to the tenth driving sub-line 52-10, and the second end of the tenth auxiliary sub-line 72-10 extends toward the second main pad 12, and is connected to the second main pad 12. The non-functional solder joint 7-1 on the 7th row and 1st column on the pad 12 is connected. In this way, the tenth driving sub-line can be connected to the two second pads on the second main pad by using the tenth auxiliary sub-line to form a "two-to-one" connection.

In an exemplary embodiment, at least one functional soldering point may be provided between the functional soldering point connected to the second driving signal line and the non-functional soldering point connected to the auxiliary line connected to the second driving signal line .

In an exemplary embodiment, the driving signal line as the main transmission line is connected to the functional pad on the pad, and the auxiliary line as the transmission branch line is connected to the non-functional pad on the pad. Since the non-functional solder joints on the pads of the existing structure are usually idle, auxiliary lines can be set to connect the non-functional solder joints. In the present disclosure, the connection structure of two solder points corresponding to one signal line is formed by setting signal wires on the main flexible plate to connect functional solder joints, and setting auxiliary wires to connect non-functional solder joints. If there is an empty solder joint in one solder joint, signal transmission can also be guaranteed, which improves the reliability of signal transmission through the pad.

In an exemplary embodiment, each driving sub-line can be provided with n auxiliary sub-lines, and the driving sub-line can be connected to n+1 solder points on the pad by using n auxiliary sub-lines to form an "n+1 to one ", n is a positive integer greater than 1. For example, for n=1, each driving sub-line can be provided with an auxiliary sub-line, and the driving sub-line can be connected to two pads on the pad by using one auxiliary sub-line to form a "two-to-one" connection. For another example, for n=2, each driving sub-line can be provided with two auxiliary sub-lines, and the driving sub-line can be connected to three solder points on the pad by using the two auxiliary sub-lines to form a "three-to-one" connection Way.

In an exemplary embodiment, the number of auxiliary sub-lines disposed on the plurality of driving sub-lines may be the same or may be different, which is not limited by the present disclosure.

FIG. 12 is a schematic plan view of a bridging flexible board in a flexible printed circuit board according to an exemplary embodiment of the present disclosure. In an exemplary embodiment, the bridging flexible board may at least include a first bridging pad 21 , a second bridging pad 22 and a plurality of connection lines 81 . The first bridging pad 21 may include a plurality of third pads, the second bridging pad 22 may include a plurality of fourth pads, the first ends of the multiple connecting lines 81 and the multiple first ends of the first bridging pad 21 The three welding points are correspondingly connected, and the second ends of the plurality of connection lines 81 are correspondingly connected with the plurality of fourth welding points of the second bridge pad 22 .

In an exemplary embodiment, the first bridging pad 21 can adopt the arrangement shown in FIG. 9a to arrange the third solder joints, including 25 solder joints, and the 25 solder joints can be arranged in 7 rows and 7 columns. array of solder joints.

In an exemplary embodiment, the bridging flexible board may further include at least one third auxiliary line 73 and at least one fourth auxiliary line 74 . A first end of the third auxiliary line 73 is connected to the connection line 81 , and a second end of the third auxiliary line 73 is connected to the third pad of the first bridge pad 21 . A first end of the fourth auxiliary line 74 is connected to the connection line 81 , and a second end of the third auxiliary line 73 is connected to the fourth soldering point of the second bridge pad 22 .

In an exemplary embodiment, the plurality of third solder joints may include at least one third functional solder joint located inside the solder joint array and at least one third non-functional solder joint located outside the solder joint array, and the plurality of fourth The solder joints may include at least one fourth functional solder joint located inside the solder joint array and at least one fourth non-functional solder joint located outside the solder joint array. A first end of the connecting wire 81 is connected to a third functional soldering point of the first bridge pad 21 , and a second end of the connecting wire 81 is connected to a fourth functional soldering point of the second bridge pad 22 . A first end of the third auxiliary line 73 is connected to the connection line 81 , and a second end of the third auxiliary line 73 is connected to at least one third non-functional soldering point of the first bridge pad 21 . A first end of the fourth auxiliary line 74 is connected to the connection line 81 , and a second end of the fourth auxiliary line 74 is connected to a fourth non-functional solder point of the second bridge pad 22 .

FIG. 13 is an enlarged view of area C in FIG. 12 , and FIG. 14 is an enlarged view of area D in FIG. 12 . Taking 5 connecting lines, the structure shown in Figure 9a for the first bridge pad and the structure shown in Figure 9b for the second bridge pad as an example, the connection between the connecting wires and the third soldering point and the fourth soldering point respectively will be described in detail. Condition. As shown in Figure 13 and Figure 14, the five connection lines may include a first connection sub-line 81-1, a second connection sub-line 81-2, a third connection sub-line 81-3, and a fourth connection sub-line 81-4 and the fifth connecting sub-line 81-5, the five third auxiliary lines may include the eleventh auxiliary sub-line 73-11, the twelfth auxiliary sub-line 73-12, the thirteenth auxiliary sub-line 73-13, the tenth auxiliary sub-line The four auxiliary sub-lines 73-14 and the fifteenth auxiliary sub-line 73-15, the five fourth auxiliary lines may include the sixteenth auxiliary sub-line 74-16, the seventeenth auxiliary sub-line 74-17, the eighteenth auxiliary sub-line A sub-line 74-18, a nineteenth auxiliary sub-line 74-19 and a twentieth auxiliary sub-line 74-20.

In an exemplary embodiment, the first end of the first connection sub-line 81-1 is connected to the functional pad 3-3 in the third row and third column on the first bridge pad 21, and the first connection sub-line 81-1 The second end of 1 is connected to the functional pad 3 - 3 in the third row and third column on the second bridge pad 22 . The first end of the eleventh auxiliary sub-line 73-11 is connected to the first connecting sub-line 81-1, and the second end of the eleventh auxiliary sub-line 73-11 extends toward the first bridge pad 21, and is connected to the first The non-functional pads 1 - 1 in the first row and the first column on the bridge pad 21 are connected. The first end of the sixteenth auxiliary sub-line 74-16 is connected to the first connection sub-line 81-1, and the second end of the sixteenth auxiliary sub-line 74-16 extends toward the second bridge pad 22, and is connected to the second The non-functional pads 1 - 1 in the first row and the first column on the bridge pad 22 are connected. In this way, the first end of the first connection sub-wire can be connected to the two third pads on the first bridge pad by using the eleventh auxiliary sub-wire to form a "two-to-one" connection mode. The first connection sub-wire The second end of the second terminal can be connected to the two fourth pads on the second bridging pad by using the sixteenth auxiliary sub-wire to form a "two-to-one" connection.

In an exemplary embodiment, the first end of the second connection sub-line 81-2 is connected to the functional pad 3-5 in the third row and fifth column on the first bridge pad 21, and the second connection sub-line 81-2 The second end of 2 is connected to the functional pad 3 - 5 in row 3 and column 5 on the second bridge pad 22 . The first end of the twelfth auxiliary sub-line 73-12 is connected to the second connection sub-line 81-2, and after the second end of the twelfth auxiliary sub-line 73-12 extends toward the first bridge pad 21, it is connected to the first The non-functional pads 1-7 in the first row and the seventh column on the bridge pad 21 are connected. The first end of the seventeenth auxiliary sub-line 74-17 is connected to the second connection sub-line 81-2, and the second end of the seventeenth auxiliary sub-line 74-17 extends toward the second bridge pad 22, and then connects with the second bridge pad 22. The non-functional solder joints 1-7 in row 1 and column 7 on pad 22 are connected. In this way, the first end of the second connection sub-wire can be connected to the two third pads on the first bridge pad by using the twelfth auxiliary sub-wire, forming a "two-to-one" connection. The second end of the second connection sub-wire can be connected to the two fourth pads on the second bridge pad by using the seventeenth auxiliary sub-wire to form a "two-to-one" connection.

In an exemplary embodiment, the first end of the third connection sub-line 81-3 is connected to the functional pad 4-4 in the fourth row and fourth column on the first bridge pad 21, and the third connection sub-line 81-3 The second end of 3 is connected to the functional pad 4 - 4 in the fourth row and fourth column on the second bridge pad 22 . The first end of the thirteenth auxiliary sub-line 73-13 is connected to the third connecting sub-line 81-3, and after the second end of the thirteenth auxiliary sub-line 73-13 extends toward the first bridge pad 21, it is connected to the first The non-functional solder joints 3 - 7 in the third row and seventh column on the bridge pad 21 are connected. The first end of the eighteenth auxiliary sub-line 74-18 is connected to the third connection sub-line 81-3, and the second end of the eighteenth auxiliary sub-line 74-18 extends toward the second bridge pad 22, and connects with the second The non-functional pads 3 - 7 in the third row and seventh column on the bridging pad 22 are connected. In this way, the first end of the third connecting sub-wire can be connected to the two third pads on the first bridge pad by using the thirteenth auxiliary sub-wire, forming a "two-to-one" connection. The second end of the third connection sub-wire 81-3 can be connected to the two fourth pads on the second bridge pad by using the eighteenth auxiliary sub-wire, forming a "two-to-one" connection.

In an exemplary embodiment, the first end of the fourth connection sub-wire 81-4 is connected to the functional pad 5-5 in the fifth row and fifth column on the first bridge pad 21, and the fourth connection sub-wire 81-4 The second end of 4 is connected to the functional pad 5 - 5 in row 5 and column 5 on the second bridge pad 22 . The first end of the fourteenth auxiliary sub-line 73-14 is connected to the fourth connecting sub-line 81-4, and after the second end of the fourteenth auxiliary sub-line 73-14 extends toward the first bridge pad 21, it is connected to the first The non-functional solder joints 7 - 7 in the seventh row and seventh column on the bridge pad 21 are connected. The first end of the nineteenth auxiliary sub-line 74-19 is connected to the fourth connecting sub-line 81-4, and after the second end of the nineteenth auxiliary sub-line 74-19 extends toward the second bridge pad 22, it is connected to the second The non-functional pads 7 - 7 in the seventh row and seventh column on the bridging pad 22 are connected. In this way, the first end of the fourth connection sub-wire can be connected to the two third pads on the first bridge pad by using the fourteenth auxiliary sub-wire, forming a "two-to-one" connection. The second end of the fourth connection sub-wire can be connected to the two fourth pads on the second bridge pad by using the nineteenth auxiliary sub-wire to form a "two-to-one" connection.

In an exemplary embodiment, the first end of the fifth connection sub-line 81-5 is connected to the functional pad 5-3 in the fifth row and third column on the first bridge pad 21, and the fifth connection sub-line 81-5 The second end of 5 is connected to the functional pad 5 - 3 in row 5 and column 3 on the second bridge pad 22 . The first end of the fifteenth auxiliary sub-line 73-15 is connected to the fifth connection sub-line 81-5, and the second end of the fifteenth auxiliary sub-line 73-15 extends toward the first bridging pad 21, and is The non-functional solder joint 7 - 1 in row 7 and column 1 on the bridge pad 21 is connected. The first end of the twentieth auxiliary sub-line 74-20 is connected to the fifth connection sub-line 81-5, and after the second end of the twentieth auxiliary sub-line 74-20 extends toward the second bridge pad 22, it is connected to the second The non-functional pads 7 - 1 in row 7 and column 1 on the bridge pad 22 are connected. In this way, the first end of the fifth connection sub-wire can be connected to the two third pads on the first bridge pad by using the fifteenth auxiliary sub-wire to form a "two-to-one" connection. The second end of the fifth connection sub-wire 81 - 5 can be connected to the two fourth pads on the second bridge pad by using the twentieth auxiliary sub-wire to form a "two-to-one" connection.

In an exemplary embodiment, at least one functional soldering point may be provided between the functional soldering point connected with the connecting wire and the non-functional soldering point connected with the auxiliary wire connected to the connecting wire.

In an exemplary embodiment, the connection line as the main transmission line is connected to the functional pads on the pad, and the auxiliary line as the branch line is connected to the non-functional pads on the pad. Since the non-functional solder joints on the pads of the existing structure are usually idle, auxiliary lines can be set to connect the non-functional solder joints. In the present disclosure, by setting connecting wires on the bridging flexible plate to connect functional soldering points, and setting auxiliary wires to connect non-functional soldering points, a connection structure in which two soldering points correspond to one connecting wire is formed, and redundancy of soldering point connection is realized, even if there are If there is an empty solder joint in one solder joint, signal transmission can also be guaranteed, which improves the reliability of signal transmission through the pad.

In an exemplary embodiment, each connection sub-line can be provided with n auxiliary sub-lines, and the driving sub-line can be connected to n+1 solder points on the pad by using n auxiliary sub-lines to form an "n+1 to one ", n is a positive integer greater than 1. For example, for n=1, each connection sub-line can be provided with an auxiliary sub-line, and the connection sub-line can be connected to two solder points on the pad by using one auxiliary sub-line to form a "two-to-one" connection mode. As another example, for n=2, each connection sub-line can be provided with two auxiliary sub-lines, and the connection sub-line can be connected with three solder points on the pad by using the two auxiliary sub-lines to form a "three-to-one" connection Way.

In an exemplary embodiment, the number of auxiliary sub-lines provided on the plurality of connecting sub-lines may be the same or different, which is not limited in the present disclosure.

In a double-layer bridge-type flexible printed circuit board, usually a signal line is connected to a functional soldering point of the main pad, and a connecting line is connected to a functional soldering point of the bridge pad, and the bridge After the functional soldering point of the pad is welded to the functional soldering point of the main pad, the signal lines on the main flexible board are connected through the bridging flexible board. For example, the connection relationship between the first driving signal line and the second driving signal line on the main flexible board is: the first driving signal line is connected to the pad 3-3 on the first main pad, and the pad on the first main pad is connected to 3-3. The point 3-3 is connected to the solder point 3-3 on the first bridge pad, the solder point 3-3 on the first bridge pad is connected to the first end of the connecting line, and the second end of the connecting line is connected to the second bridge The solder point 3-3 on the pad is connected, the solder point 3-3 on the second bridge pad is connected to the solder point 3-3 on the second main pad, and the solder point 3-3 on the second main pad Connect with the second driving signal line.

The present disclosure provides a flexible printed circuit board, at least one signal line is connected to a functional pad of the main pad, and at least one auxiliary line connected to the signal line is connected to a non-functional pad of the main pad Above, at least one connection line is connected to a functional pad of the bridge pad, and at least one auxiliary line connected to the connection line is connected to a non-functional pad of the bridge pad. After soldering the functional solder joints and non-functional solder joints of the bridge pad to the functional solder joints and non-functional solder joints of the main pad, not only the signal lines on the main flexible board are connected through the bridge flexible board , and each signal line has at least two solder joint connection channels between the main pad and the bridge pad. For example, the connection relationship between the first driving signal line and the second driving signal line on the main flexible board is: the first driving signal line is connected to the pad 3-3 on the first main pad, and the auxiliary line of the first driving signal line Connect to pad 1-1 on the first main pad. The solder point 3-3 on the first main pad is connected to the solder point 3-3 on the first bridge pad, and the solder point 1-1 on the first main pad is connected to the solder point 1 on the first bridge pad. -1 connection. The soldering point 3-3 on the first bridge pad is connected to the first end of the connecting wire, and the soldering point 1-1 on the first bridge pad is connected to the auxiliary wire of the connecting wire. The second end of the connection line is connected to the solder point 3-3 on the second bridge pad, and the auxiliary line of the connection line is connected to the solder point 1-1 on the second bridge pad. The solder point 3-3 on the second bridge pad is connected to the solder point 3-3 on the second main pad, and the solder point 1-1 on the second bridge pad is connected to the solder point 1 on the second main pad. -1 connection. The pad 3-3 on the second main pad is connected to the second driving signal line, and the pad 1-1 on the second main pad is connected to the auxiliary line of the second driving signal line. The present disclosure realizes the redundancy of solder joint connection by setting at least two solder joint connection channels between the main pad and the bridge pad. The reliability of the disk transmission signal.

As shown in FIGS. 12 to 14 , in an exemplary embodiment, the bridging flexible board may include a connection line area 210 , a first pad area 211 and a second pad area 212 , and the connection line area 210 may be disposed on the first pad area. Between the pad area 211 and the second pad area 212 .

In an exemplary embodiment, the connection line region 210 may be provided with a plurality of connection lines 81, the shape of the connection lines 81 may be a straight line or a broken line extending along the first direction D1, and the plurality of connection lines 81 may be arranged in the second direction D2. Set in sequence. The first ends of the plurality of connection lines 81 extend to the first pad area 211 and are connected to the plurality of third pads correspondingly, and the second ends of the plurality of connection lines 81 extend to the second pad area 212 to connect with the plurality of third pads. Four solder joints correspond to connections.

In an exemplary embodiment, the first pad area 211 may include a first pad area 211-1 and a first dispensing area 211-2, and the first pad area 211-1 is configured to set a first bridging pad , the first dispensing area 211-2 can be arranged on the periphery of the first solder joint area 211-1, and the surface of the first dispensing area 211-2 is dispensed by a glue dispenser, and the first dispensing area 211- 2 to form a dispensing layer.

In an exemplary embodiment, the second pad area 212 may include a second pad area 212-1 and a second glue dispensing area 212-2, and the second pad area 212-1 is configured to set a second bridging pad , the second dispensing area 212-2 can be arranged on the periphery of the second solder joint area 212-1, and the surface of the second dispensing area 212-2 is dispensed by a glue dispenser, and in the second dispensing area 212- 2 to form a dispensing layer.

In an exemplary embodiment, the first pad area 211-1 and the second pad area 212-1 may be referred to as Ball Grid Array (BGA for short) areas.

In an exemplary embodiment, the first connection point 91 where the third auxiliary line 73 is connected to the connection line 81 may be located in the first glue dispensing area 211-2. Since the first glue dispensing area is provided with a dispensing layer, the first glue dispensing area is not easily deformed. By setting the first connection point in the first glue dispensing area in the present disclosure, the deformation can be avoided from affecting the third connection point, and the connection is improved. reliability.

In an exemplary embodiment, the second connection point 92 where the fourth auxiliary line 74 is connected to the connection line 81 may be located in the second glue dispensing area 212-2. Since the second glue dispensing area is provided with a dispensing layer, the second glue dispensing area is not easy to be deformed. By setting the second connection point in the second glue dispensing area in the present disclosure, the deformation can be avoided from affecting the second connection point, and the connection is improved. reliability.

FIG. 15 is a schematic plan view of another bridging flexible board in the flexible printed circuit board of the exemplary embodiment of the present disclosure. In the exemplary embodiment, the structure of the bridging flexible board in this exemplary embodiment is basically similar to the structure of the bridging flexible board shown in FIG. The connection point 91 may be located in the connection line area 210 , and the second connection point 92 where the fourth auxiliary line 74 is connected to the connection line 81 may be located in the connection line area 210 .

In an exemplary embodiment, since the connection line area is far away from the BGA area, the surface of the connection line area is relatively flat, and the present disclosure can prevent deformation from affecting the first connection by arranging the first connection point and the second connection point in the connection line area. point and a second connection point, improving connection reliability.

FIG. 16 is a schematic plan view of another bridging flexible board in the flexible printed circuit board according to an exemplary embodiment of the present disclosure, illustrating the structure of the first pad area 211 and part of the connection line area 210 . As shown in Figure 16, in the exemplary embodiment, the structure of the bridging flexible board in this exemplary embodiment is basically similar to the structure of the bridging flexible board shown in Figure 12, the difference is that the bridging flexible board is also provided with at least one through hole 90 .

In an exemplary embodiment, the via hole 90 may be disposed in the first pad area, and/or, may be disposed in the BGA area of the second pad area.

In an exemplary embodiment, the via hole 90 may be located between adjacent third pads, and/or, may be located between adjacent fourth pads.

In an exemplary embodiment, the shape of the through hole 90 may include any one or more of the following: triangle, square, rectangle, rhombus, parallelogram, trapezoid, pentagon, hexagon, the present disclosure is not limited here .

In an exemplary embodiment, the size of the through hole 90 may be less than or equal to 0.1 mm, and the size of the through hole refers to the maximum value of the distance between any two points on the edge of the through hole. For example, when the shape of the through hole is circular, the diameter of the through hole may be about 0.05 mm, 0.08 mm, or 0.1 mm.

In an exemplary embodiment, the second center-to-center distance L2 between the through hole 90 and the adjacent third solder joint may be about 0.55 mm to 0.65 mm, and/or, the through hole 90 and the adjacent fourth solder joint The second center-to-center distance L2 may be about 0.55 mm to 0.65 mm, and the second center-to-center distance L2 is the distance between the geometric center of the through hole and the geometric center of the solder joint.

In an exemplary embodiment, the adjacent third welding points or the adjacent fourth welding points may be adjacent in the first direction D1, or may be adjacent in the second direction D2.

FIG. 17 is a schematic cross-sectional structure diagram of a flexible circuit board according to an exemplary embodiment of the present disclosure, which is a cross-sectional view along the line A-A in FIG. 16 . As shown in FIG. 17 , in a plane perpendicular to the flexible circuit board, the bridge flexible board 20 is arranged on the main flexible board 10, and the bridge flexible board 20 may include a bridge shielding layer 420 arranged on the main flexible board 10, a bridge shield layer 420 arranged on the bridge The shielding layer 420 is away from the first bridging green oil layer 421 on the side of the main flexible board 10, the first bridging conductive layer 422 is set on the side of the first bridging green oil layer 421 away from the main flexible board 10, and the first bridging conductive layer 422 is set on the side away from the main flexible board 10. The bridging substrate layer 423 on one side of the main flexible board 10, the second bridging conductive layer 424 arranged on the side of the bridging substrate layer 423 away from the main flexible board 10, and the second bridging conductive layer 424 arranged on the side away from the main flexible board 10 The second bridging green oil layer 425.

In an exemplary embodiment, the first pad region 211 (or the second pad region 212) is provided with a plurality of solder joint vias, and the bridge shielding layer 420, the first bridge green oil layer 421, the second solder joint via hole A bridging conductive layer 422, a bridging base material layer 423, a second bridging conductive layer 424, and a second bridging green oil layer 425 are removed, and solder joint vias are configured to accommodate solder 93 to form solder joints, so that the bridging flexible board 20 and the second bridging green oil layer 425 are removed. The main flexible board 10 is connected.

In an exemplary embodiment, the first pad region 211 (or the second pad region 212) may be provided with at least one through hole 90, the through hole 90 may be located between the solder vias, and the bridge shield in the through hole 90 Layer 420, first bridging green oil layer 421, first bridging conductive layer 422, bridging substrate layer 423, second bridging conductive layer 424, and second bridging green oil layer 425 are removed. In an exemplary embodiment, the through hole 90 is configured as a gas circulation channel to discharge the gas between the solder 93 during the vacuum reflow process, improve the exhaust efficiency during the reflow process, and reduce the air bubbles in the solder and between the solder , to reduce the occurrence of false welding.

In an exemplary embodiment, the first bridge conductive layer 422 may be called a ground copper layer, and the second bridge conductive layer 424 may be called a wiring layer.

In an exemplary embodiment, the main flexible board 10 may include an outer shielding layer 411, a cover layer 412 disposed on the outer shielding layer 411, a first main conductive layer 413 disposed on the side of the covering layer 412 away from the outer shielding layer 411, a set The main substrate layer 414 on the side of the first main conductive layer 413 away from the outer shielding layer 411, the second main conductive layer 415 arranged on the side of the main substrate layer 414 away from the outer shielding layer 411, and the second main conductive layer 415 arranged on the side of the second main conductive layer 415 is the main green oil layer 416 on the side away from the outer shielding layer 411 and the main shielding layer 417 is arranged on the side of the main green oil layer 416 away from the outer shielding layer 411 . In an exemplary embodiment, the main shielding layer 417 and the main green oil layer 416 are provided with a plurality of main board via holes, the main shielding layer 417 and the main green oil layer 416 in the main board via holes are removed, and the position of the main board via holes is the same as that of the bridge The positions of the via holes on the solder joints on the flexible board 20 are corresponding, and the via holes bridging the solder joints on the flexible board 20 can expose the second main conductive layer 415, so that the solder 93 filled in the via holes of the solder joints will bridge the flexible board 20 Connect with the main flexible board 10.

FIG. 18 is a schematic cross-sectional view of another flexible circuit board according to an exemplary embodiment of the present disclosure, which is a cross-sectional view along the line A-A in FIG. 16 . As shown in FIG. 18, the main structure of the flexible circuit board in this exemplary embodiment is basically similar to that shown in FIG. remove.

In an exemplary embodiment, the bridging flexible board 20 may include a first bridging green oil layer 421 disposed on the main flexible board 10 , and a first bridging conductive layer 422 disposed on the side of the first bridging green oil layer 421 away from the main flexible board 10 , the bridging substrate layer 423 arranged on the side of the first bridging conductive layer 422 away from the main flexible board 10, the second bridging conductive layer 424 arranged on the side of the bridging substrate layer 423 away from the main flexible board 10, and the second bridging conductive layer 424 arranged on the second bridge The conductive layer 424 is away from the second bridging green oil layer 425 on the side of the main flexible board 10 .

In an exemplary embodiment, the main flexible board 10 may include an outer shielding layer 411, a cover layer 412 disposed on the outer shielding layer 411, a first main conductive layer 413 disposed on the side of the covering layer 412 away from the outer shielding layer 411, a set The main substrate layer 414 on the side of the first main conductive layer 413 away from the outer shielding layer 411, the second main conductive layer 415 arranged on the side of the main substrate layer 414 away from the outer shielding layer 411, and the second main conductive layer 415 arranged on the side of the second main conductive layer 415 away from the main green oil layer 416 on the side of the outer shielding layer 411.

In an exemplary embodiment, the first pad area 211 (or the second pad area 212) is provided with a plurality of solder joint vias, and the first pad area 211 (or the second pad area 212) may be provided with at least A through hole 90.

In a flexible circuit board structure, the main flexible board usually includes a main shielding film, and the main shielding film is arranged on the side of the main green oil layer away from the outer shielding layer, and the bridging flexible board usually includes a bridging shielding film, and the bridging shielding film is arranged on the first The side of the bridging green oil layer close to the main flexible board forms a structure in which the bridging shielding film is in contact with the main shielding film. The flexible circuit board proposed in this exemplary embodiment removes the main shielding film of the main flexible board and the bridging shielding film of the bridging flexible board, forming a direct contact between the main green oil layer of the main flexible board and the first bridging green oil layer of the bridging flexible board The structure can not only reduce the overall thickness of the flexible circuit board, but also prevent the deformation caused by the cohesive pulling of the shielding film, improve the surface flatness, and improve the bonding degree of the main flexible board and the bridge flexible board. Compared with the existing flexible circuit board structure, the overall thickness of the flexible circuit board in this exemplary embodiment after removing the main shielding film and the bridging shielding film can be reduced by about 12 μm to 20 μm. Since there is no functional connection between the main flexible board and the bridging flexible board except for the first pad area and the second pad area, removing the main shielding film and the bridging shielding film will not affect the shielding function.

FIG. 19 is a schematic cross-sectional view of yet another flexible circuit board according to an exemplary embodiment of the present disclosure, which is a cross-sectional view along the line A-A in FIG. 16 . As shown in FIG. 19, the main structure of the flexible circuit board in this exemplary embodiment is basically similar to that shown in FIG. layer is removed.

In an exemplary embodiment, the bridging flexible board 20 may include a bridging shielding layer 420 disposed on the main flexible board 10, a first bridging green oil layer 421 disposed on the side of the bridging shielding layer 420 away from the main flexible board 10, a first bridging green oil layer 421 disposed on the second A bridging green oil layer 421 away from the first bridging conductive layer 422 on the side of the main flexible board 10, a bridging substrate layer 423 arranged on the side of the first bridging conductive layer 422 away from the main flexible board 10, a bridging substrate layer 423 arranged on the side away from the bridging substrate layer 423 The second bridging conductive layer 424 on the side of the main flexible board 10 and the second bridging green oil layer 425 disposed on the side of the second bridging conductive layer 424 away from the main flexible board 10 .

In an exemplary embodiment, the first bridging conductive layer 422 is only disposed on the connection line region 210, the first bridging conductive layer 422 of the first pad region 211 (or the second pad region 212) is removed, and only the solder joints remain The via copper ring at the via hole is configured to ensure the connection reliability between the bridging flexible board 20 and the main flexible board 10 .

In an exemplary embodiment, the solder joint in the first pad area 211 (or the second pad area 212 ) close to the connection line area 210 is connected to the side of the first bridge conductive layer 422 in the connection line area 210 close to the solder joint. The distance L3 between the edges can be greater than or equal to 1.0 mm, so as to reduce the level difference near the first pad area 211 (or the second pad area 212 ) and improve the flatness of this area.

In an exemplary embodiment, the first pad area 211 (or the second pad area 212) is provided with a plurality of solder joint vias, and the first pad area 211 (or the second pad area 212) may be provided with at least A through hole 90, the structure of the main flexible board is basically the same as the structure of the main flexible board shown in FIG. 17 .

In the structure of a flexible circuit board, an opening is usually provided in the pad area, the ground copper layer in the opening is removed, the ground copper layer outside the opening is retained, and a plurality of solder joints are arranged in the ground copper opening. The minimum distance between the opening edges of the ground copper is about 0.3mm. The inventors of the present application have found through research that since the pad area still retains a large area of ground copper layer, the spacing between solder joints is small, and the pad area is easily deformed during reflow soldering. In this exemplary embodiment, by removing the ground copper layer in the pad area, the area of the solder joint area is increased, and the distance between the solder joints is increased, which not only reduces the risk of deformation in the pad area, but also can Set through holes between them to improve the exhaust efficiency during reflow soldering, reduce air bubbles in and between solders, and reduce the occurrence of false soldering. Compared with the existing flexible circuit board structure, the flexible circuit board in this exemplary embodiment improves soldering reliability, reduces the risk of failure, and improves product yield. In addition, this exemplary embodiment effectively reduces the overall thickness of the flexible circuit board. Compared with the existing flexible circuit board structure, this exemplary embodiment removes the ground copper layer in the pad area, and the overall thickness of the flexible circuit board can be reduced. The reduction is about 8 μm to about 12 μm.

FIG. 20 is a schematic cross-sectional view of another bridging flexible board according to an exemplary embodiment of the present disclosure, which is a cross-sectional view taken along the line A-A in FIG. 16 . As shown in FIG. 20, the main structure of the flexible circuit board in this exemplary embodiment is basically similar to that shown in FIG. Removal, the ground copper layer of the first pad region 211 (or the second pad region 212 ) is removed.

In an exemplary embodiment, the main flexible board 10 may include an outer shielding layer 411, a cover layer 412 disposed on the outer shielding layer 411, a first main conductive layer 413 disposed on the side of the covering layer 412 away from the outer shielding layer 411, a set The main substrate layer 414 on the side of the first main conductive layer 413 away from the outer shielding layer 411, the second main conductive layer 415 arranged on the side of the main substrate layer 414 away from the outer shielding layer 411, and the second main conductive layer 415 arranged on the side of the second main conductive layer 415 away from the main green oil layer 416 on the side of the outer shielding layer 411. In an exemplary embodiment, the main green oil layer 416 is provided with a plurality of green oil via holes, the main green oil layer 416 in the green oil via holes is removed, and the positions of the green oil via holes are in line with the solder joints on the bridging flexible board 20 The positions of the via holes are corresponding, and the solder joint via holes on the bridging flexible board 20 can expose the second main conductive layer 415 , so that the solder 93 filled in the solder joint via holes connects the bridging flexible board 20 to the main flexible board 10 .

In an exemplary embodiment, the first pad area 211 (or the second pad area 212) is provided with a plurality of solder joint vias, and the first bridge green oil layer 421 and the first bridge conductive layer 422 in the solder joint vias , the bridging substrate layer 423, the second bridging conductive layer 424 and the second bridging green oil layer 425 are removed, and the solder joint vias are configured to accommodate the solder 93 to form solder joints, so that the bridging flexible board 20 is connected to the main flexible board 10 .

In an exemplary embodiment, the first pad region 211 (or the second pad region 212 ) may be provided with at least one through hole 90 , and the through hole 90 may be located between the pad via holes. In an exemplary embodiment, the through hole 90 is configured as a gas circulation channel to discharge the gas between the solder 93 during the vacuum reflow process, improve the exhaust efficiency during the reflow process, and reduce the air bubbles in the solder and between the solder , to reduce the occurrence of false welding.

In this exemplary embodiment, by removing the ground copper layer in the pad area, the area of the solder joint area is increased, and the distance between the solder joints is increased, which not only reduces the risk of deformation in the pad area, but also can Set through holes between them to improve the exhaust efficiency during reflow soldering, reduce air bubbles in and between solders, and reduce the occurrence of false soldering. Compared with the existing flexible circuit board structure, the flexible circuit board in this exemplary embodiment improves soldering reliability, reduces the risk of failure, and improves product yield. In addition, the present exemplary embodiment minimizes the overall thickness of the flexible circuit board by removing the main shielding film of the main flexible board and the bridging shielding film of the bridging flexible board, and removing the ground copper layer in the pad area, compared with Compared with the existing flexible circuit board structure, the overall thickness of the flexible circuit board in this exemplary embodiment can be reduced by about 20 μm to 32 μm.

Exemplary embodiments of the present disclosure also provide a display touch device, including a touch display panel and the aforementioned flexible printed circuit board, the touch display panel may include an active area and a binding on one side of the active area The binding area may include a binding pin area, and the flexible printed circuit board is connected to the binding pin area.

In an exemplary embodiment, the display touch device of the present disclosure may be any product or component with a display function such as a mobile phone, a tablet computer, a television, a monitor, a notebook computer, a digital camera, a digital photo frame, and a navigator.

Although the embodiments disclosed in the present disclosure are as above, the described content is only an embodiment adopted for understanding the present disclosure, and is not intended to limit the present invention. Any person skilled in the art can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present disclosure, but the patent protection scope of the present invention must still be based on the The scope defined by the appended claims shall prevail.

Claims

A flexible printed circuit board, comprising a main flexible board and a bridging flexible board, the main flexible board at least includes a first main pad, a second main pad, at least one first signal line and at least one second signal line, so The bridging flexible board at least includes a first bridging pad, a second bridging pad, and at least one connection line; the first main pad includes at least two first solder points, and the second main pad includes at least two The second welding point, the first signal line is connected to a first welding point, and the second signal line is connected to a second welding point; the first bridging pad includes at least two third welding points, so The second bridging pad includes at least two fourth welding points, the first end of the connecting line is connected to a third welding point, and the second end of the connecting line is connected to a fourth welding point; the first A soldering point is connected to the third soldering point through soldering, and the second soldering point is connected to the fourth soldering point through soldering; the flexible printed circuit board also includes a first auxiliary line, a second auxiliary line, a first Any one or more of the three auxiliary lines and the fourth auxiliary line; the first end of the first auxiliary line is connected to the first signal line, and the second end of the first auxiliary line is connected to another first Solder point connection; the first end of the second auxiliary line is connected to the second signal line, and the second end of the second auxiliary line is connected to another second solder point; the first end of the third auxiliary line One end is connected to the connection line, the second end of the third auxiliary line is connected to another third welding point; the first end of the fourth auxiliary line is connected to the connection line, and the fourth auxiliary line The second end of the wire is connected to another fourth pad.
The flexible printed circuit board according to claim 1, wherein the main flexible board includes a touch drive circuit and at least one terminal, the first end of the first signal line is connected to the terminal, and the first signal line The second end of the line is connected to the first pad of the first main pad, the first end of the second signal line is connected to the touch driving circuit, and the second end of the second signal line is connected to the The second solder joint of the second main pad is connected.
The flexible printed circuit board according to claim 1, wherein the first main pad includes a plurality of first soldering points, the plurality of first soldering points are arranged in a matrix to form a soldering point array, and the plurality of first soldering points including at least one first functional solder joint located inside the solder joint array and at least one first non-functional solder joint located outside the solder joint array, the first signal line and the first functional solder joint point connection, the first auxiliary line is connected to the first non-functional soldering point.
The flexible printed circuit board according to claim 1, wherein the second main pad includes a plurality of second soldering points, the plurality of second soldering points are arranged in a matrix to form a soldering point array, and the plurality of second soldering points including at least one second functional solder joint located inside the solder joint array and at least one second non-functional solder joint located outside the solder joint array, the second signal line is connected to the second functional solder joint point connection, the first auxiliary line is connected to the second non-functional welding point.
The flexible printed circuit board according to claim 1, wherein the first bridging pad includes a plurality of third soldering points, the plurality of third soldering points are arranged in a matrix to form a soldering point array, and the plurality of third soldering points including at least one third functional soldering point located inside the soldering point array and at least one third non-functional soldering point located outside the soldering point array, the connection line is connected to the third functional soldering point , the third auxiliary line is connected to the third non-functional solder joint.
The flexible printed circuit board according to claim 1, wherein the second bridging pad includes a plurality of fourth welding points, the plurality of fourth welding points are arranged in a matrix to form a welding point array, and the plurality of fourth welding points including at least one fourth functional soldering point located inside the soldering point array and at least one fourth non-functional soldering point located outside the soldering point array, the connection line is connected to the fourth functional soldering point , the fourth auxiliary line is connected to the fourth non-functional solder joint.
The flexible printed circuit board according to claim 1, wherein the bridging flexible board comprises a connection line area, a first pad area and a second pad area, and the connection line area is arranged on the first pad area and the second pad area; the connecting line is set in the connecting line area, the first bridge pad is set in the first pad area, and the second bridge pad is set in the first pad area The second pad area; the first connection point where the third auxiliary line is connected to the connection line is located in the connection line area, and/or the second connection point where the fourth auxiliary line is connected to the connection line located in the connection line area.
The flexible printed circuit board according to claim 1, wherein the bridging flexible board comprises a connection line area, a first pad area and a second pad area, and the connection line area is arranged on the first pad area Between the second pad area, the connection line is arranged in the connection line area; the first pad area includes a first pad area and a first dispensing area, and the first pad area is provided with the first pad area The first bridging pad, the first dispensing area is arranged on the periphery of the first pad area; the second pad area includes a second soldering area and a second dispensing area, the second The second bridging pad is provided in the pad area, and the second dispensing area is arranged on the periphery of the second pad area; the first connection point where the third auxiliary line is connected to the connection line is located at the The first dispensing area, and/or, the second connection point where the fourth auxiliary line connects with the connection line is located in the second dispensing area.
The flexible printed circuit board according to claim 1, wherein the center-to-center distance between adjacent first soldering points is 1.05 mm to 1.25 mm; and/or, the center-to-center distance between adjacent second soldering points is 1.05mm to 1.25mm; and/or, the center-to-center distance between adjacent third solder joints is 1.05mm to 1.25mm; and/or, the center-to-center distance between adjacent fourth solder joints is 1.05mm to 1.25mm mm.
The flexible printed circuit board according to claim 1, wherein the first bridging pad further comprises at least one through hole disposed between the adjacent third soldering points; and/or, The second bridging pad further includes at least one through hole disposed between the adjacent fourth pads.
The flexible printed circuit board according to claim 10, wherein the size of the through hole is less than or equal to 0.1 mm, and the size of the through hole refers to the maximum distance between any two points on the edge of the through hole.
The flexible printed circuit board according to claim 10, wherein, the center distance between the through hole and the adjacent third solder joint is 0.55 mm to 0.65 mm; and/or, the through hole and the adjacent fourth The center distance between solder joints is 0.55mm to 0.65mm.
The flexible printed circuit board according to any one of claims 1 to 12, wherein, in a plane perpendicular to the flexible printed circuit board, the bridging flexible board is arranged on the main flexible board, and the bridging flexible board includes The first bridging green oil layer arranged on the main flexible board, the first bridging conductive layer arranged on the side of the first bridging green oil layer away from the main flexible board, the first bridging conductive layer arranged on the side far away from the first bridging conductive layer The bridging substrate layer on one side of the main flexible board, the second bridging conductive layer arranged on the side of the bridging substrate layer away from the main flexible board, and the second bridging conductive layer arranged on the side away from the main flexible board The second bridging green oil layer on one side; the first bridging conductive layer is only provided in the connecting line area of the bridging flexible board.
The flexible printed circuit board according to claim 13, wherein, the edge of the third solder joint close to the side of the connection line region is connected to the first bridging conductive layer in the connection line region close to the third solder joint. The distance between the edges on one side of the points is greater than or equal to 1.0 mm, and/or, the edge of the fourth solder joint close to the connecting line area is close to the first bridging conductive layer in the connecting line area The distance between edges on one side of the fourth welding spot is greater than or equal to 1.0 mm.
The flexible printed circuit board according to claim 13, wherein the main flexible board comprises a shielding layer, a covering layer disposed on the shielding layer, a first first disposed on a side of the covering layer away from the shielding layer. The main conductive layer, the main substrate layer arranged on the side of the first main conductive layer away from the shielding layer, the second main conductive layer arranged on the side of the main substrate layer away from the shielding layer, and the The second main conductive layer is away from the main green oil layer on the side of the shielding layer; the first bridging green oil layer of the bridging flexible board is in direct contact with the main green oil layer.
A display touch device, comprising a touch display panel and the flexible printed circuit board according to any one of claims 1 to 15, the touch display panel comprising an effective area and a binding on one side of the effective area An area, the binding area includes a binding pin area, and the flexible printed circuit board is connected to the binding pin area.